1. Field of the Invention
The invention relates to a temperature detecting circuit, and more particularly, to a temperature detecting circuit capable of compensating an offset of a reference voltage.
2. Description of Related Art
In modern integrated circuits, for various applications, a temperature detecting circuit is often required to be disposed in chips. For example, the temperature detecting circuit can be used to detect whether temperature is overly high in order to activate overheat protection mechanism for circuit to thereby ensure work performance of the circuit.
In the conventional technical field, a temperature independent reference voltage is usually used while temperature dependent circuit elements are disposed in the circuit. Electric property parameters of the temperature dependent elements may include a positive temperature coefficient or may also include a negative temperature coefficient instead. A temperature at the time may be detected by comparing the electric property parameters (e.g., voltages) which change with temperature variation as provided by said circuit elements with the temperature independent reference voltage.
However, referring to FIG. 1, which is a waveform diagram of a temperature detection in prior art. In the conventional technical field, an offset within a specific range (e.g., a range represented by dash lines) may occur on a reference voltage Vref, and the same condition may also occur on voltages V1 to V3 provided by the temperature dependent circuit elements. Accordingly, certain errors may occur on a comparison result of the reference voltage Vref and the voltages V1 to V3, resulting in an inaccurate temperature detection.